1. Field of the Invention
This invention relates to direct access storage devices (DASD's). More particular, it relates to DASD's wherein a rotating storage medium interacts with a head so as to store and/or retrieve information.
2. Background Art
An important design parameter for disk drives is the number of tracks per inch (TPI) that can be repeatably read and written by the heads. The role of the head positioning servo system is to ensure that the heads follow the track within a given error. One of the leading causes of this error can be from vibration of the drive produced by the rotation of an imbalanced spindle.
Until now, significant expense and time have been devoted to balancing spindles to reduce the amplitude of this vibration. This increases cost by requiring that very precisely balanced parts be produced, or that each spindle be individually balanced, an inherently time consuming and costly procedure.